Identifying a bath-induced Bose liquid in interacting spin-boson models

TL;DR

This paper explores how a bath-induced Bose metal phase can emerge in a one-dimensional interacting spin-boson model, revealing a new quantum phase influenced by dissipation.

Contribution

It demonstrates the existence of a bath-induced Bose metal phase in an interacting spin-boson system, extending understanding of dissipative quantum phases.

Findings

Bose metal phase occurs away from half filling.

Phase is compressible, gapless, and conducting but not superfluid.

Quantum Monte Carlo method applicable to various open bosonic systems.

Abstract

We study the ground state phase diagram of a one-dimensional hard-core bosonic model with nearest-neighbor interactions (XXZ model) where every site is coupled Ohmically to an independent but identical reservoir, hereby generalizing spin-boson models to interacting spin-boson systems. We show that a bath-induced Bose metal phase can occur in the ground state phase diagram away from half filling. This phase is compressible, gapless, and conducting but not superfluid. At haf-filling, only a Luttinger liquid and a charge density wave are found. The phase transition between them is of Kosterlitz-Thouless type where the Luttinger parameter takes a non-universal value.The applied quantum Monte Carlo method can be used for all open bosonic and unfrustrated spin systems, regardless of their dimension, filling factor and spectrum of the dissipation as long as the quantum system couples to the bath via the density operators.